1. Field of the Invention
The present invention relates to a vehicle provided with a curtain air bag.
2. Description of the Related Art
FIG. 5A is a view schematically showing the inside of a vehicle, around a seat installed within the vehicle. As shown in FIG. 5A, a seat 50 on which the occupant is to be seated, and a seat belt 51 for protecting the occupant from, e.g., a car accident, are installed within the vehicle.
The seat belt 51 in FIG. 5A is a lap and diagonal belt, which is installed together with a seat belt anchor 52a and a seat belt retractor (belt windup device), not shown, within the vehicle. The occupant seated on the seat 50 inserts a tongue 53 into a buckle 54 to fasten the seat belt 51 so that the occupant can be secured on the seat 50.
In recent years, vehicles of the type that a seat belt anchor 52b is fixed to a roof side rail 56 as shown in FIG. 5B have become more common as compared with vehicles of the type that the seat belt anchor 52a is fixed to a center pillar 55 as shown in FIG. 5A. In the case where the seat belt anchor 52b is fixed to the roof side rail 56, the seat belt anchor 52b is fixed at a location of the roof side rail 56, which is at the rear of the center pillar 55.
The location of the seat belt anchor has been changed as described above for the following reason. In the case of the type that the seat belt anchor 52a is fixed to the center pillar 55 located substantially on the side of the occupant, a gap is formed between the seat belt 51 and the occupant seated on the seat 50 when the seat 50 is moved rearward along the length of the vehicle, and hence the occupant may not be sufficiently secured, whereas in the case of the type that the seat belt anchor 52b is fixed to a location of the roof side rail 56, which is at the rear of the occupant, the occupant can be sufficiently secured without being affected by the movement of the seat 50.
An air bag as well as the seat belt can be used as a device which protects the occupant from, e.g., a car accident. In particular, a curtain air bag installed on the side of the vehicle serves as an occupant protective device for protecting the occupant from impact applied to the side of the vehicle.
FIG. 6 is a view schematically showing the structure of the curtain air bag in a deployed condition. If impact is applied to the side of the vehicle, gas ejected from an inflator 60 flows into a gas intake passage 59 constituting the curtain air bag (FIG. 6 shows the curtain air bag 57 in a deployed condition) stowed along the roof side rail 56. The gas which has flown into the gas intake passage 59 having a substantially linear shape, inflates a plurality of inflating parts 58, causing the curtain air bag 57 to be deployed over the whole of the side of the seated occupant 63, so that the occupant 63 can be protected from the impact applied to the side of the vehicle.
Mounting parts 61 are protruded at predetermined intervals from the upper edge of the curtain air bag 57. At the mounting parts 61, the curtain air bag 57 is fixed to the roof side rail 56 via fastening members 62 such as bolts to endure the reaction caused by the intake of high-pressure gas during deployment.
FIG. 7 is a view schematically showing the curtain air bag installed on the roof side rail as viewed from the inside of the vehicle. FIG. 7 shows a part of the curtain air bag, where there is no inflating part, the curtain air bag being comprised of the gas intake passage 59 installed along the roof side rail, and a plurality of inflating parts (refer to the inflating parts 58 appearing in FIG. 6) installed at regular intervals in the gas intake passage 59.
As shown in FIG. 7, the curtain air bag mounting part 61 is fixed to a roof side rail inner 66, which constitutes the vehicle inner side of the roof side rail, via the fastening member 62 such as a bolt, so that the curtain air bag can be installed on the roof side rail. When the curtain air bag is in a stowed condition, the gas intake passage 59 is stored in a roof side trim, not shown, in the state of being retracted along the roof side rail 56.
On this occasion, an obstacle such as the center pillar 55 lies below the curtain air bag in the inflating direction thereof, the curtain air bag may not be smoothly deployed. For this reason, a rising bracket is additionally disposed between the curtain air bag and the obstacle so that the air bag can be smoothly deployed. FIG. 7 shows an example where a center pillar rising bracket 67 is disposed for the center pillar 55 as the obstacle.
The seat belt and the curtain air bag as above can be typically used as devices for protecting the occupant, but in the case where both the seat belt anchor and the curtain air bag are installed on the roof side rail, the following problem arises.
Specifically, the seat belt anchor 52b is installed on the roof side rail 56, and the curtain air bag 57 (mounting parts 57) is fixed on the roof side rail 56 at a plurality of locations and in the direction of the length of the vehicle, and further, the rising bracket is disposed where necessary. This complicates the inner side of the roof side rail, restricts locations where parts are mounted, and increases the man-hour for assembly (refer to Japanese Laid-Open Patent Publication (Kokai) No. 2002-264762)
Further, if the seat belt anchor 52b is installed on the roof side rail 56, and the curtain air bag 57 (mounting parts 61) is installed along the roof side rail 56 and in the direction of the length of the vehicle, the gas intake passage 59 inflated by the inflow of gas from the inflator 60 and the seat belt anchor 52b interfere with each other in the event of air bag deployment. Consequently, the seat belt anchor 52a inhibits the gas intake passage 59a from sufficiently inflating, and the flow of gas in the gas intake passage 59b as well as the flow of gas into the inflating parts 58 cannot be realized at a sufficient speed, and therefore, the curtain air bag cannot be smoothly deployed.